12620681 has 4 divisors (see below), whose sum is σ = 13363092. Its totient is φ = 11878272.
The previous prime is 12620677. The next prime is 12620687. The reversal of 12620681 is 18602621.
It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18602621 = 61 ⋅304961.
It can be written as a sum of positive squares in 2 ways, for example, as 5107600 + 7513081 = 2260^2 + 2741^2 .
It is a cyclic number.
It is not a de Polignac number, because 12620681 - 22 = 12620677 is a prime.
It is a super-2 number, since 2×126206812 = 318563177807522, which contains 22 as substring.
It is a Duffinian number.
It is a self number, because there is not a number n which added to its sum of digits gives 12620681.
It is not an unprimeable number, because it can be changed into a prime (12620687) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 371180 + ... + 371213.
It is an arithmetic number, because the mean of its divisors is an integer number (3340773).
Almost surely, 212620681 is an apocalyptic number.
It is an amenable number.
12620681 is a deficient number, since it is larger than the sum of its proper divisors (742411).
12620681 is an equidigital number, since it uses as much as digits as its factorization.
12620681 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 742410.
The product of its (nonzero) digits is 1152, while the sum is 26.
The square root of 12620681 is about 3552.5597813408. The cubic root of 12620681 is about 232.8239197227.
The spelling of 12620681 in words is "twelve million, six hundred twenty thousand, six hundred eighty-one".
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